The DF-4 (CSS-3) is an intermediate-range, surface-based, liquid propellant ballistic missile. It has a range of 4,750 km (2,952 miles) and carries a 2,200 kg payload. Its payload is designed to accommodate a single nuclear warhead with a yield between 1 and 3 MT. Its accuracy is approximately 1,500 m CEP. It has a length of 28.0 m, a body diameter of 2.25 m, and a launch weight of 82,000 kg. It uses a two-stage liquid propellant engine.

The DF-4 began development in the early 1960s and its design essentially took place in parallel with the DF-3 (CSS-2). The first test launch occurred in 1970, but eventually was re-tested in the late 1970s following the change in the required range. Early trials tried to perfect silo and road-based systems, but these did not succeed and the DF-4 missiles were stored in caves prior to launch. The missile entered service in 1980, and it is believed that around 20 to 35 missiles were produced. It was expected to be replaced by the DF-31 (CSS-9) between 2001 and 2005, but this has not been confirmed, and it is presumed that the DF-4 remains in service.The DF-4 eventually led to a three-stage civilian derivative known as the Long March-1 (LM-1 or CZ-1). This was the vehicle used to launch the first Chinese Satellite in 1970. 1